This invention relates to a method for producing metal carbide grade powders in which the surface area of the powders is increased prior to application of the wax binder. This results in an even distribution of the wax binder on the powder particles. The grade powder product thus produced is essentially free of micropores, that is, pores which measure from about 10 to about 25 micrometers in diameter and essentially free of macropores, that is, pores greater than about 25 micrometers in diameter after sintering at a temperature of from about 1350.degree. C. to about 1540.degree. C.
In the production of metal carbide grade powders there is a problem of uneven distribution of the wax binder on the powder particle surfaces. The uneven distsribution results from the fact that in attritor milling of the powders with wax, new surface area is produced due to the comminution of the highly agglomerated and/or polycrystalline metal carbide starting material. The larger the starting particle size, the higher the proportion of new surface produced. The new surface cannot be readily coated with the wax additive blend during milling as the solid state of the wax and the polar nature of the water make the redistribution of the wax very unlikely. As a result, densified articles made from these powders exhibit porosity and void defects, which adversely affect the strength and wear properties of the article.